Mold produced design for a thumb screw



FIG. 1 is a perspective view of a mold produced design for a thumb screw showing my new design.

FIG. 2 is a rear view thereof.

FIG. 3 is a front view thereof.

FIG. 4 is a left side view thereof; and,

FIG. 5 is a right side view thereof.

The broken lines showing a threaded shank are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a mold produced design for a thumb screw, as shown and described. 